Arsonist gunman kills two US firefighters

Attacker behind New York state shooting served prison time for killing his grandmother.

Two volunteer firefighters have been shot dead and two others left wounded after they were ambushed by a lone gunman at a blaze apparently set as a trap in New York state.

Lieutenant Michael Chiapperini and Tomasz Kaczowka were killed when 62-year-old William Spangler opened fire at emergency responders arriving at the scene of a house fire, shortly before 6:00 am local time (1100GMT) on Monday in the suburb of Rochester.

"This is still an active investigation, but I will say at first blush that it appears that it was a trap, that there was a car in a house that it was engulfed in flames, probably set by Mr Spangler, who later waited and shot the first responders," said Webster police chief Gerald Pickering.

Spangler had spent 17 years in prison after killing his grandmother in 1981. He may have stolen the guns used in the shooting, said police.

"We have to keep in mind that Spangler was a convicted felon," said Chief Pickering.

"So he is not allowed to possess weapons, so, did he legally possess these weapons? No, but we had all kinds of weapons larcenies, both in town and around the county, and in Wayne County as of late, so I don't know were those weapons came from, but we are certainly going to find out."

Spangler shot himself after attacking the firefighting crew, said police. He died on the scene.

"It's really heartbreaking, for these families and these people, and so close to a holiday where we're supposed to love each other," said one Webster resident. Bunches of flowers and handwritten notes have been left at the scene of the attack.

The two wounded firefighters, Joseph Hofsetter and Theodore Scardino, were listed in guarded condition at a local hospital, according to the Democrat and Chronicle newspaper.

The deadly shooting in Newtown, Connecticut, has revived debate in US on the country's gun laws [GALLO/GETTY]

More than 30 residents were evacuated as firefighters battled to contain the blaze.

The shooter, Adam Lanza, killed his mother at their home before heading to the school, where he eventually took his own life.

Lax gun laws

The recent shootings have revived debate in the US on the country's gun laws, which are far more lax than in most other developed nations.

Barack Obama, the US president, said he would support a new bill to ban assault rifles, and has put Vice President Joe Biden in charge of a panel looking at a wide range of other measures, from school security to mental health.

Democratic Senator Dianne Feinstein has pledged to introduce a bill in January that would ban at least 100 military-style semi-automatic assault weapons, and would curb the transfer, importation and the possession of such arms.

The US has suffered an increase of gun violence over the past three decades, including 62 mass shooting incidents since 1982.